Marine Biodiversity in the Caribbean: Regional Estimates and Distribution Patterns

This paper provides an analysis of the distribution patterns of marine biodiversity and summarizes the major activities of the Census of Marine Life program in the Caribbean region. The coastal Caribbean region is a large marine ecosystem (LME) characterized by coral reefs, mangroves, and seagrasses, but including other environments, such as sandy beaches and rocky shores. These tropical ecosystems incorporate a high diversity of associated flora and fauna, and the nations that border the Caribbean collectively encompass a major global marine biodiversity hot spot. We analyze the state of knowledge of marine biodiversity based on the geographic distribution of georeferenced species records and regional taxonomic lists. A total of 12,046 marine species are reported in this paper for the Caribbean region. These include representatives from 31 animal phyla, two plant phyla, one group of Chromista, and three groups of Protoctista. Sampling effort has been greatest in shallow, nearshore waters, where there is relatively good coverage of species records; offshore and deep environments have been less studied. Additionally, we found that the currently accepted classification of marine ecoregions of the Caribbean did not apply for the benthic distributions of five relatively well known taxonomic groups. Coastal species richness tends to concentrate along the Antillean arc (Cuba to the southernmost Antilles) and the northern coast of South America (Venezuela – Colombia), while no pattern can be observed in the deep sea with the available data. Several factors make it impossible to determine the extent to which these distribution patterns accurately reflect the true situation for marine biodiversity in general: (1) highly localized concentrations of collecting effort and a lack of collecting in many areas and ecosystems, (2) high variability among collecting methods, (3) limited taxonomic expertise for many groups, and (4) differing levels of activity in the study of different taxa

Gibraltar experiment: A plan for dynamic and kinematic investigations of strait mixing, exchange and turbulence

In the past few years, focus has shifted to the study of how the dynamical constraints for flow through a narrow and shallow strait act to control the amount of exchange between the Atlantic and Mediterranean basins. To investigate the dynamics of flow through a strait, a year-long field experiment has been designed to measure the flows through the Strait of Gibraltar, including their time variability over tidal to seasonal time scales, and to assess the importance of friction, mixing, rotation, and nonlinear processes in controlling the exchange through the strait. This field program, called the Gibraltar experiment, will be carried out by a group of American, Spanish, Moroccan, Canadian and French scientists during the period from fall 1985 to fall 1986

Correlations between seabirds and ocenic fronts around the Pribilof Islands, Alaska

Located on the extensive continental shelf of the Bering Sea, the Pribilof Islands, Alaska are the site of one of the largest breeding colonies of seabirds in the northern hemisphere. During summer these islands are surrounded by a front that separates vertically homogeneous waters from well stratified waters farther seaward. We studied the front with hydrographic data and the bird distributions with concurrent counts during summer 1977 and spring, summer and fall 1978. Murres (Uria lomvia and U. aalge) sitting on the water aggregated near the front during summer 1977 and probably during summer 1978. Other species, such as northern fulmars (Fulmarus glacialis) and auklets (Aethia pusilla and A. cristatella) were unaffected by the front. We hypothesize that the aggregation of the murres was related to an enhanced availability of their food near the front. © 1983